package com.atguigu.cart.interceptor;

/**
 * @Classname CartInterceptor
 * @Description TODO
 * @Date 2024/7/12 16:52
 * @Created by 369502594
 */

import com.atguigu.cart.constant.CartConstant;
import com.atguigu.cart.vo.UserInfoTo;
import com.atguigu.common.constant.AuthServerConstant;
import com.atguigu.common.vo.MemberRespVo;
import org.apache.commons.lang.StringUtils;
import org.springframework.stereotype.Component;
import org.springframework.web.servlet.HandlerInterceptor;
import org.springframework.web.servlet.ModelAndView;

import javax.servlet.http.Cookie;
import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse;
import javax.servlet.http.HttpSession;
import java.util.UUID;

/**
 * 在执行目标方法，判断用户的登录状态。并封装传递给controller目标请求
 */
@Component
public class CartInterceptor implements HandlerInterceptor {

    public static ThreadLocal<UserInfoTo> threadLocal = new ThreadLocal<>();

    /**
     * 目标方法执行之前
     * @param request current HTTP request
     * @param response current HTTP response
     * @param handler chosen handler to execute, for type and/or instance evaluation
     * @return
     * @throws Exception
     */
    @Override
    public boolean preHandle(HttpServletRequest request, HttpServletResponse response, Object handler) throws Exception {
        UserInfoTo userInfoTo = new UserInfoTo();
        HttpSession session = request.getSession();
        MemberRespVo member = (MemberRespVo) session.getAttribute(AuthServerConstant.LOGIN_USER);
        if (member != null){
            // 用户登录
            userInfoTo.setUserId(member.getId());
        }else {

        }

        // 判断请求是否带有user-key的cookie
        Cookie[] cookies = request.getCookies();
        if(cookies !=null && cookies.length > 0){
            for (Cookie cookie : cookies) {
                // user-key
                String name = cookie.getName();
                if (name.equals(CartConstant.TEMP_USER_COOKIE_NAME)){
                    userInfoTo.setUserkey(cookie.getValue());
                    userInfoTo.setTempUser(true);
                }
            }
        }
        // 如果没有临时用户cookie，需要分配一个临时用户
        if (StringUtils.isEmpty(userInfoTo.getUserkey())){
            String uuid = UUID.randomUUID().toString();
            userInfoTo.setUserkey(uuid);
        }
        // 目标方法执行之前
        threadLocal.set(userInfoTo);
        return true;
    }

    /**
     * 业务执行之后;分配临时用户,让浏览器保存
     * @param request current HTTP request
     * @param response current HTTP response
     * @param handler the handler (or {@link HandlerMethod}) that started asynchronous
     * execution, for type and/or instance examination
     * @param modelAndView the {@code ModelAndView} that the handler returned
     * (can also be {@code null})
     * @throws Exception
     */
    @Override
    public void postHandle(HttpServletRequest request, HttpServletResponse response, Object handler, ModelAndView modelAndView) throws Exception {
        UserInfoTo userInfoTo = threadLocal.get();

        // 如果没有临时用户，一定要保存一个临时用户，新建一个user-key的cookie
        if (!userInfoTo.isTempUser()){
            // 持续的延长临时用户的过期时间
            Cookie cookie = new Cookie(CartConstant.TEMP_USER_COOKIE_NAME, userInfoTo.getUserkey());
            cookie.setDomain("gulimall.com");
            cookie.setMaxAge(CartConstant.TEMP_USER_COOKIE_TIMEOUT);
            response.addCookie(cookie);
        }

    }
}
